Fox Aaron, Kwapinski Witold, Griffiths Bryan S, Schmalenberger Achim
Department of Life Sciences, University of Limerick, Limerick, Ireland.
FEMS Microbiol Ecol. 2014 Oct;90(1):78-91. doi: 10.1111/1574-6941.12374. Epub 2014 Jul 21.
Plants rely on microorganisms to mobilize organically and inorganically bound sulfur (S) and phosphorus (P) in which the plant can then readily utilize. The aim of this study was to investigate the role of S- and P-mobilizing bacteria in plant growth promotion in biochar-amended soil, which has been rarely investigated so far. Pot experiments of Lolium perenne were established on S and P limited soil with 1% or 2% biochar (Miscanthus × giganteus) or without biochar (control) for a period of 126 days. Both biochar amendments resulted in significant plant growth promotion. Rhizobacteria capable of growing with (1) S from aromatic sulfonates, (2) P from phosphate esters, (3) P from phosphonates, and (4) P from tri-calcium phosphates as sole source of S or P, respectively, were significantly more abundant in the biochar treatments. 16S rRNA gene-based rhizobacteria community analysis revealed a significant biochar treatment effect. Abundance of nematodes feeding on bacteria was also significantly increased in the biochar treatments. Diversity analysis of rhizospheric asfA and phnJ genes revealed broad sequence diversities in bacterial sulfonate and phosphonate-mineralizing capabilities. These findings suggest that biochar amendment enhances microbially mediated nutrient mobilization of S and P resulting in improved plant growth.
植物依靠微生物来活化有机和无机结合态的硫（S）和磷（P），之后植物便能轻易利用这些元素。本研究的目的是调查硫和磷活化细菌在生物炭改良土壤中促进植物生长方面的作用，而这方面的研究至今仍很少。在硫和磷含量有限的土壤上开展多年生黑麦草的盆栽试验，设置添加1%或2%生物炭（巨芒草）或不添加生物炭（对照）的处理，试验为期126天。两种生物炭添加处理均显著促进了植物生长。在生物炭处理中，分别能够以（1）芳基磺酸盐中的硫、（2）磷酸酯中的磷、（3）膦酸盐中的磷以及（4）磷酸三钙中的磷作为唯一硫源或磷源生长的根际细菌明显更为丰富。基于16S rRNA基因的根际细菌群落分析显示生物炭处理具有显著效果。在生物炭处理中，以细菌为食的线虫数量也显著增加。根际asfA和phnJ基因的多样性分析揭示了细菌磺酸盐和膦酸盐矿化能力方面广泛的序列多样性。这些发现表明，生物炭改良增强了微生物介导的硫和磷养分活化，从而促进了植物生长。
